Return Streamreader to Beginning

Return StreamReader to Beginning

You need to seek on the stream, like you did, then call DiscardBufferedData on the StreamReader. Documentation here:

Edit: Adding code example:

Stream s = new MemoryStream();
StreamReader sr = new StreamReader(s);
// later... after we read stuff
s.Position = 0;
sr.DiscardBufferedData();        // reader now reading from position 0

Return StreamReader to Beginning when his BaseStream has BOM

    //pass all 3 tests
    void ResetStream(ref StreamReader sr){
        sr.Read(); //ensure that BOM is detected if configured to do so
        sr.BaseStream.Position=0;
        sr=new StreamReader(sr.BaseStream, sr.CurrentEncoding, false);
    }

Do I need to reset a stream(C#) back to the start?

When you read a stream to the end, specifically with StreamReader's ReadToEnd method, you have to Seek it back to the beginning. This can be done like so:

StreamReader sr = new StreamReader(stream);
sr.ReadToEnd();
stream.Seek(0, SeekOrigin.Begin); //StreamReader doesn't have the Seek method, stream does.
sr.ReadToEnd(); // This now works

How to make the StreamReader read from the start of the textfile

This should be working, and I am guessing that there is something else happening along the way. Once you open a reader, it moves down and must be reset if you want it back to reading from the top. Maybe your reference was left open elsewhere (but that is assuming that the posted code has something happening that was not posted), or used before this piece of code?

However, you can always force the position to the top to verify this theory. If after this code, you still are at the 14th line, then it might be the file itself somehow?

reader.DiscardBufferedData(); 
reader.BaseStream.Seek(0, SeekOrigin.Begin); 
reader.BaseStream.Position = 0;

c# - StreamReader and seeking

Yes you can, see this:

var sr = new StreamReader("test.txt");
sr.BaseStream.Seek(2, SeekOrigin.Begin); // Check sr.BaseStream.CanSeek first

Update:
Be aware that you can't necessarily use sr.BaseStream.Position to anything useful because StreamReader uses buffers so it will not reflect what you actually have read. I guess you gonna have problems finding the true position. Because you can't just count characters (different encodings and therefore character lengths). I think the best way is to work with FileStream´s themselves.

Update:
Use the TGREER.myStreamReader from here:
http://www.daniweb.com/software-development/csharp/threads/35078
this class adds BytesRead etc. (works with ReadLine() but apparently not with other reads methods)
and then you can do like this:

File.WriteAllText("test.txt", "1234\n56789");

long position = -1;

using (var sr = new myStreamReader("test.txt"))
{
    Console.WriteLine(sr.ReadLine());

    position = sr.BytesRead;
}

Console.WriteLine("Wait");

using (var sr = new myStreamReader("test.txt"))
{
    sr.BaseStream.Seek(position, SeekOrigin.Begin);
    Console.WriteLine(sr.ReadToEnd());
}

Can I return a StreamReader from a method?

Yes, of course. It's not a great idea, though - you're creating the StreamReader in one method, and closing it in another. It's better practice to create and close the reader in one method.

Strange question mark, when setting StreamReader to beginning

It's very likely that the file starts with a byte order mark (BOM) which is being ignored by the reader initially, but then not when you "rewind" the stream.

While you could create a new reader, or even just replace it after reading it, I think it would be better to just avoid reading the file twice to start with:

foreach (var question in File.ReadLines(text, Encoding.Unicode))
{
    Console.WriteLine(question);
    string response = Console.ReadLine();
    potentialEmployee.Responses.Add(question, response);
}

That's shorter, simpler, more efficient code that also won't display the problem you asked about.

If you want to make sure you can read the whole file before asking any questions, that's easy too:

string[] questions = File.ReadAllLines(text, Encoding.Unicode);
foreach (var question in questions)
{
    Console.WriteLine(question);
    string response = Console.ReadLine();
    potentialEmployee.Responses.Add(question, response);
}

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